[The effects of patient-controlled epidural analgesia with background infusion after abdominal surgery].
D000005:Abdomen / Q000601:surgery*; D000368:Aged; D015360:Analgesia, Epidural; D016058:Analgesia, Patient-Controlled / Q000009:adverse effects / Q000379:methods*; D000701:Analgesics, Opioid / Q000008:administration & dosage; D000779:Anesthetics, Local / Q000008:administration & dosage; D002045:Bupivacaine / Q000008:administration & dosage; D005260:Female; D005283:Fentanyl / Q000008:administration & dosage; D006801:Humans; D007260:Infusion Pumps; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010149:Postoperative Pain / Q000188:drug therapy*
D000701:Analgesics, Opioid; D000779:Anesthetics, Local; D005283:Fentanyl; D002045:Bupivacaine